From 0d4e6f203a2052b5ffd0de78466cf2b9caef8e15 Mon Sep 17 00:00:00 2001
From: Jaremy Creechley <creechley@gmail.com>
Date: Fri, 25 Aug 2023 15:08:19 -0700
Subject: [PATCH] switch to smartptrs

---
 datastore/databuffer.nim | 73 +++++++++-------------------------------
 1 file changed, 16 insertions(+), 57 deletions(-)

diff --git a/datastore/databuffer.nim b/datastore/databuffer.nim
index d1e78aa..3ce4651 100644
--- a/datastore/databuffer.nim
+++ b/datastore/databuffer.nim
@@ -1,93 +1,52 @@
 
 
 
-import std/os
-import std/locks
-import std/atomics
+# import std/atomics
+import threading/smartptrs
 
-import events
 
 type
-  DataBuffer* = object
-    cnt: ptr int
+  DataBufferHolder* = object
     buf: ptr UncheckedArray[byte]
     size: int
   
+  DataBuffer* = SharedPtr[DataBufferHolder]
   KeyBuffer* = DataBuffer
   ValueBuffer* = DataBuffer
   StringBuffer* = DataBuffer
   CatchableErrorBuffer* = object
     msg: StringBuffer
 
-proc `$`*(data: DataBuffer): string =
-  if data.buf.isNil:
-    result = "nil"
-  else:
-    let sz = min(16, data.size)
-    result = newString(sz + 2)
-    copyMem(addr result[1], data.buf, sz)
-    result[0] = '<'
-    result[^1] = '>'
-
-proc `=destroy`*(x: var DataBuffer) =
+proc `=destroy`*(x: var DataBufferHolder) =
   ## copy pointer implementation
-  if x.buf != nil and x.cnt != nil:
-    let res = atomicSubFetch(x.cnt, 1, ATOMIC_ACQUIRE)
-    if res == 0:
-      when isMainModule or true:
-        echo "buffer: FREE: ", repr x.buf.pointer, " ", x.cnt[]
-      deallocShared(x.buf)
-      deallocShared(x.cnt)
-    else:
-      when isMainModule:
-        echo "buffer: decr: ", repr x.buf.pointer, " ", x.cnt[]
+  if x.buf != nil:
+    when isMainModule or true:
+      echo "buffer: FREE: ", repr x.buf.pointer
+    deallocShared(x.buf)
 
-proc `=copy`*(a: var DataBuffer; b: DataBuffer) =
-  ## copy pointer implementation
-
-  # do nothing for self-assignments:
-  if a.buf == b.buf: return
-  `=destroy`(a)
-  discard atomicAddFetch(b.cnt, 1, ATOMIC_RELAXED)
-  a.size = b.size
-  a.buf = b.buf
-  a.cnt = b.cnt
-  when isMainModule:
-    echo "buffer: Copy: repr: ", b.cnt[],
-          " ", repr a.buf.pointer, 
-          " ", repr b.buf.pointer
-
-proc incrAtomicCount*(a: DataBuffer) =
-  let res = atomicAddFetch(a.cnt, 1, ATOMIC_RELAXED)
-proc unsafeGetAtomicCount*(a: DataBuffer): int =
-  atomicLoad(a.cnt, addr result, ATOMIC_RELAXED)
-
-proc len*(a: DataBuffer): int = a.size
+proc len*(a: DataBuffer): int = a[].size
 
 proc new*(tp: typedesc[DataBuffer], size: int = 0): DataBuffer =
-  let cnt = cast[ptr int](allocShared0(sizeof(result.cnt)))
-  cnt[] = 1
-  DataBuffer(
-    cnt: cnt,
-    buf: cast[typeof(result.buf)](allocShared0(size)),
+  newSharedPtr(DataBufferHolder(
+    buf: cast[typeof(result[].buf)](allocShared0(size)),
     size: size,
-  )
+  ))
 
 proc new*[T: byte | char](tp: typedesc[DataBuffer], data: openArray[T]): DataBuffer =
   ## allocate new buffer and copies indata from openArray
   ## 
   result = DataBuffer.new(data.len)
   if data.len() > 0:
-    copyMem(result.buf, unsafeAddr data[0], data.len)
+    copyMem(result[].buf, unsafeAddr data[0], data.len)
 
 proc toSeq*[T: byte | char](a: DataBuffer, tp: typedesc[T]): seq[T] =
   result = newSeq[T](a.len)
-  copyMem(addr result[0], unsafeAddr a.buf[0], a.len)
+  copyMem(addr result[0], unsafeAddr a[].buf[0], a.len)
 
 proc toString*(data: DataBuffer): string =
   result = newString(data.len())
   if data.len() > 0:
-    copyMem(addr result[0], unsafeAddr data.buf[0], data.len)
+    copyMem(addr result[0], unsafeAddr data[].buf[0], data.len)
 
 proc toCatchable*(data: CatchableErrorBuffer): ref CatchableError =
   result = (ref CatchableError)(msg: data.msg.toString())